Emergency response organizations increasingly depend on wireless communication technology to provide communication during emergencies. Disadvantageously, however, emergencies often result in damage to, or sometimes even destruction of, existing network infrastructure, thereby preventing communications between emergency personnel. In other words, the existing communications infrastructure lacks survivability. Furthermore, even if portions of the existing communications infrastructure do survive the emergency, the existing communications infrastructure may not be able to handle the increased traffic load typical during emergencies. Specifically, remaining portions of the existing communication infrastructure may be overloaded as emergency personnel, and the general public, attempt various types of communications. Such deficiencies became clear during the events of Sep. 11, 2001, and again during the events of Hurricane Katrina.
In fixed networks, visiting users to the fixed network are granted access using a pair of Authentication, Authorization, and Accounting (AAA) servers; namely, a home AAA server and a visitor AAA server. Specifically, in fixed networks, in order to grant access to visiting users, the visited AAA server operates as a proxy server that communicates with the visitor's home AAA server. Disadvantageously, while this existing procedure is reliable for fixed networks, it is quite unreliable for non-fixed, ad-hoc networks. The procedure is unreliable for non-fixed, ad-hoc networks because there is no guarantee that the visitor AAA server will be available throughout the lifetime of the ad-hoc network or that connectivity to the visitor AAA server will be maintained throughout the lifetime of the ad-hoc network.